Modelling the dispersal of larval Japanese sardine, Sardinops melanostictus, by the Kuroshio Current in 1993 and 1994   总被引：1，自引：1，他引：0  

M. HEATH  H. ZENITANI  Y. WATANABE  R. KIMURA  & M. ISHIDA 《Fisheries Oceanography》1998,7(3-4):335-346

Acoustic Doppler current profiler (ADCP) data collected during routine monitoring surveys of the distribution and abundance of Japanese sardine larvae ( Sardinops melanostictus ) off the Pacific coast of Japan in February 1993 and 1994 were used to construct stationary average flowfields for three levels in the upper 100 m in each year. No large-scale meanders in the path of the Kuroshio Current were present in either year, but the axis of the current was closer to the coast in 1993 than in 1994. The flowfields were used to drive a particle-tracking model representing the dispersal of sardine eggs and larvae. Particles were released in accordance with the observed distribution of eggs, and their positions tracked for up to 40 days. In 1993, the model indicated that ≈ 50% of the egg production was carried north-eastwards out of the survey area into the area of the NW Pacific referred to as the Kuroshio Extension Zone. In contrast, only 5% of the egg production was exported to the Extension Zone in 1994, the remainder being retained in Japanese coastal waters. The consequences of the different dispersal patterns are discussed in relation to subsequent recruitment to the sardine stock. Based on commercial catch data, survival of the 1993 year class was 15% of that for the 1994 class. Hence, the results indicate that export of larvae to the Kuroshio Extension cannot in itself lead to successful recruitment.  相似文献   

Naupliar copepod concentrations in the spawning grounds of Japanese sardine, Sardinops melanostictus, along the Kuroshio Current     

YOSHIRO WATANABE  HIROMU ZENITANI  RYO KIMURA  CHIKAKO SATO  YUTAKA OKUMURA  HIROYA SUGISAKI  & YOSHIOKI OOZEKI 《Fisheries Oceanography》1998,7(2):101-109

Naupliar copepods were distributed at similar concentrations over the waters inshore and offshore of the Kuroshio Current off central Japan in early spring 1993 and 1994, overlapping with the distribution of early feeding larvae of Sardinops melanostictus . Although N, P, Si and chlorophyll a concentrations were higher in the waters inshore of the Kuroshio axis than in the offshore waters, the mean concentrations of nauplii were not statistically different between the two waters. Food availability for larval S. melanostictus did not seem to be different between the two waters in terms of the mean food concentrations. Using the critical food concentration (>9 nauplii L^–1) for 25% survival during 3 days after first feeding derived from a rearing experiment, percentages in number of stations or water samples with nauplii concentrations >9 nauplii L^–1 were higher in the inshore waters than in the offshore waters in both years examined. Considering that fish larvae may depend on small-scale patchiness of food for their survival, the inshore waters seemed to be more favourable for first-feeding larvae than the offshore waters.  相似文献   

Zoogeographical barriers causing discontinuous osteometrical variations in the northern treeshrew skulls     

Hideki ENDO  Truong Son NGUYEN  Dinh Duy NGUYEN  Motoki SASAKI  Junpei KIMURA  Tatsuo OSHIDA  Masaya YAGO  Ngoc Tu LY  Thi Tham NGUYEN  Masaharu MOTOKAWA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(10):1534

Morphological variation of the skull was examined in the northern treeshrew (Tupaia belangeri) from various localities across Southeast Asia. Through a multivariate analysis, the treeshrews from South Vietnam exhibited distinct morphological characteristics compared to other populations from Thailand and Laos, and Malaysia. The plots of the specimens of North Vietnam are not randomly mixed with Thailand plots segregation in the scatteregrams of canonical discriminant analysis. Since the skulls of the population from North Vietnam were morphologically similar to those form central Laos and northern and northeastern Thailand, the zoogeographical barrier effect of Mekong River was not clearly confirmed. The population of the Kanchanaburi in western Thailand is clearly smaller in size compared to the other populations. The southern border of the distribution of this species is determined by the Isthmus of Kra or Kangar-Pattani Line. In the northern treeshrew, which is distributed from southern China to Bangladesh and southern Thailand, we have detected osteometrical geographical variation driven by geography. These results indicate that the skull morphology in the Tupaia glis-belangeri complex distinctively differs in South Vietnam, western Thailand, and southern Thailand. The zoogeographical barrier and factor separating these districts are expected to clarify in the future.  相似文献   

Role of the C-Terminal Region of Vervet Monkey Polyomavirus 1 VP1 in Virion Formation     

Hiroki YAMAGUCHI  Shintaro KOBAYASHI  Junki MARUYAMA  Michihito SASAKI  Ayato TAKADA  Takashi KIMURA  Hirofumi SAWA  Yasuko ORBA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2014,76(5):637-644

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中药乳头浸蘸剂防治奶牛隐性乳房炎的研究   总被引：6，自引：0，他引：6  

木村直美  张克家  陆钢 《中国兽医杂志》2003,39(10):29-32

采用抑菌试验并考虑成膜的屏障作用，筛选中药制成奶牛乳头浸蘸剂防治奶牛隐性乳房炎。经63头252个乳区的临床试验证明。复方黄连(黄连 蜂胶 乳没)和复方大青叶(大青叶 五倍子 乳没)2个处方分别制成的中药乳头浸蘸剂，对奶牛隐性乳房炎均有较好的防冶效果。  相似文献   

Effect of elevated atmospheric CO₂ concentration on ammonia oxidizing bacteria communities inhabiting in rice roots     

Saman BOWATTE  Susumu ASAKAWA  Masumi OKADA  Kazuhiko KOBAYASHI  Makoto KIMURA 《Soil Science and Plant Nutrition》2007,53(1):32-39

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Arabidopsis SNRK2.3 protein kinase is involved in the regulation of sulfur-responsive gene expression and O-acetyl-l-serine accumulation under limited sulfur supply     

Tomoko KIMURA  Nakako SHIBAGAKI  Naoko OHKAMA-OHTSU  Hiroaki HAYASHI  Tadakatsu YONEYAMA  John P. DAVIES  Toru FUJIWARA 《Soil Science and Plant Nutrition》2006,52(2):211-220

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Soil organic matter dynamics in lands continuously cultivated with maize and soybean in Heilongjiang Province, Northeast China: Estimation from natural ¹³C abundance     

Guanghua WANG  Xiaozeng HAN  Natusko NAKAYAMA  Takeshi WATANABE  Akira WATANABE  Makoto KIMURA 《Soil Science and Plant Nutrition》2006,52(2):139-144

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Molecular characterization of methane-oxidizing bacteria associated with rice straw decomposition in a rice field     

Zhong-Jun JIA  Atsuo SUGANO  Naoko ASARI  Cho Cho TUN  Rie ISHIHARA  Susumu ASAKAWA  Makoto KIMURA 《Soil Science and Plant Nutrition》2007,53(6):729-739

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Minocycline prevents primary duck neurons from duck Tembusu virus-induced death     

Sittinee KULPRASERTSRI  Keisuke AOSHIMA  Atsushi KOBAYASHI  Takashi KIMURA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(4):734

Duck Tembusu virus (DTMUV), a neurotropic flavivirus, is a causative agent of severe neurological diseases in different birds. No approved vaccines or antiviral therapeutic treatments are available to date. The poultry industry experiences significant economic losses due to DTMUV infections. Minocycline is a second-generation semi-synthetic tetracycline analogue that is commonly used as an antimicrobial treatment. Experimental studies have indicated the successful protective effects of minocycline against neuronal cell death from neurodegenerative diseases and viral encephalitis. The aim of this study was to investigate the effects of minocycline on DTMUV infection in neurons. Primary duck neurons were treated with minocycline, which exhibited neuroprotective effects via anti-apoptotic function rather than through viral replication inhibition. Minocycline might serve as a potential effective drug in DTMUV infection.  相似文献